Vitamin K

Vitamin K, also known as the master coagulator, is an important fat-soluble vitamin. It was first discovered in 1929 by a scientist named Henrik Dam, who was researching the role and nature of cholesterol. Dam was feeding chicken with a cholesterol-free diet. After a few weeks, chickens on this diet started developing hemorrhages and started bleeding. He couldn’t repair these deficiencies by supplementing their diet with purified cholesterol. It appeared that a second compound had also been extracted from the diet, and this one was thought to be responsible for the coagulation of blood. Coagulation in German is spelled with a “k”, so, the mysterious compound was named vitamin K.

There are two primary forms of vitamin K. Phylloquinone (K1) comes from plants. Menaquinone (K2) come from animals and bacteria in the gut. There is also a synthetic form known as K3. What is the function of vitamin K? Its name comes from the German word for coagulation, and it is needed for the normal clotting cascade of blood by the synthesis of blood proteins. Vitamin K is also needed for the production of what are known as Gla proteins, which are needed for the normal production of bone proteins.

Increasing evidence shows that vitamin K may aid in the prevention of osteoporosis. It forms a protein which is found in cartilage and provides the framework on which bone is formed.

There is no true requirement for vitamin K, because we don’t know how much the gut produces. Although no recommended amount exists, an acceptable intake is 90 micrograms for women and 120 micrograms for men.

Vitamin K Deficiency and Toxicity

Vitamin K deficiency is common among breast-fed infants, because breast milk is low on vitamin K. If a baby is going to be born, make sure that baby goes to a physician relatively early and gets a vitamin K injection to prevent poor clotting.

Vitamin K can interfere with anticoagulant drugs. Antibiotics kill the bacteria that can make vitamin K, so anybody taking chronic antibiotic therapy is going to be unable to synthesize vitamin K in the gut.

There is no known toxicity of vitamin K.

Foods High in Vitamin K

1 cup kale	1000 micrograms
1 cup spinach	880 micrograms
1 cup cabbage	73 micrograms
1 cup broccoli	155 micrograms
1 cup brussels sprouts	218 micrograms